If you thought all the different HDMI standards and optional features were already confusing, it's bound to get a lot worse very soon. The reasoning behind this, according to a statement received by TFTCentral, is that HDMI 2.1 is backwards-compatible, and hence means HDMI 2.0 is no longer required.
The HDMI Licensing Administration has made it clear that all future displays are required to state support for HDMI 2.1, even if the hardware uses features no support for HDMI 2.1 features at all.
Read more on gamespot.com